FDA Issues Warning About Vetsulin Insulin
Breaking news.
Vetsulin insulin is widely used in diabetic dogs (and, occasionally, diabetic cats). I was therefore disturbed to receive the following e-mail from the American Veterinary Medical Association.
FDA-CVM Issues Alert About Problems with Vetsulin® Porcine Insulin Zinc Suspension
November 3, 2009 – The U.S. Food and Drug Administration’s Center for Veterinary Medicine, in cooperation with Intervet/Schering-Plough Animal Health, has announced that Vetsulin® may have varying amounts of crystalline zinc insulin, the active ingredient, in the formula. As a result, use of the product could result in a delay in action of the drug as well as prolonged action, which could cause difficulty in managing diabetic pets. Get more information on the AVMA web site, AVMA.org: http://www.avma.org/aa/vetsulin_091102.asp
If you administer Vetsulin to your pet, I recommend that you contact your veterinarian about this matter immediately. Unreliable insulin can lead to chronically high blood sugar in pets. Worse, it can lead to accidental insulin overdose. For information on the symptoms of insulin overdose in pets, go to my website:
You have questions. 
I was suspect that there has been an ongoing problem with this product. My dog Chip has almost died twice. I thought it was curious that I got an email from Petmeds asking how Chip was doing on his insulin, when I told them he wasn’t doing well, they just stated they were sorry to hear that. I told them in a second email that I was pretty sure it was a drug problem. They chose to ignore me. We have spent thousands of dollars on this dog trying unsuccessfully to get him regulated. When I let our vet know that vetsulin was going to be in short supply and we wanted to know what to do, he stated there was no problem with the vetsulin. I have since sent him all the information from the FDA.
Vestulin has killed my pets.
IF THIS PRODUCT IS DEFECTIVE THERE SHOULD BE A NATIONWIDE RECALL.
Suspect Vetsulin “instability” killed my cat a day after Christmas 2009. He was “stuck” on high blood sugar, was even at the vet / animal hospital. They tried everything possible to save him. CC was only 7 years old. The producer of Vetsulin isn’t very good at customer service. When CC was first diagnosed 2-1/2 years ago, I wrote to the maker of Vetsulin to ask how long a bottle of insulin is good for once I start it. They never bothered to return my message. IF THIS PRODUCT IS DEFECTIVE THERE SHOULD BE A NATIONWIDE RECALL. I WILL purse legal action against them.
In regards to those who have had problems (or suspected them) with Vetsulin in their animals it should be noted that the inconsistencies in regulation have as yet to be documented in an animal and are completely theoretical based upon the insulin chemistry. This does NOT mean that your animals might not have been affected by delayed onset of activity, delayed peak activity, and extended duration of overall effect types of symptoms. However, it does take some careful testing to verify both these symptoms AND the cause. There is no recall because there has been no proof – only laboratory testing and speculation. And on another short note, Petmeds is NOT a veterinary facility and can give owners no satisfaction regarding regulation as they are not allowed to make any medical recommendations – customer service merely is trained to ask how things are going, much like your car salesman asks you how your new ride is treating you. He isn’t a mechanic so he will HOPEFULLY tell you to address your concern to the appropriate department (e.g. your vet!).
My condolences and sympathies to those of you who have had these issues – keeping a regular dialogue with your vet is the best practice and should there be an issue I strongly recommend you keep asking until you get the right answers or get a second opinion – all the while understanding that diabetes isn’t curable and is often complicated by other diseases that are MUCH more difficult to diagnose.